Testicular morphology and cauda epididymal sperm reserves of male rats exposed to Nigerian Qua Iboe Brent crude oil

Potential negative effects of exposure to Nigerian Qua Iboe Brent crude oil on the reproductive system of male rats was investigated. Forty Sprague-Dawley rats were used for the experiment. Exposure to Nigerian Qua Iboe Brent crude oil was achieved via oral administration of increasing doses (0.1, 0.2, and 0.4 ml/rat) every other day for 4 weeks. Cauda epididymal sperm reserves and relative weights of the testes as well as histological features of the testes of rats that received the crude oil treatment were compared to those of control rats. The results described here showed a significant (p < 0.01) dose-dependent reduction in the cauda epididymal sperm reserves of rats that received crude oil treatment relative to the control group. The morphology of testes of the crude oil-exposed rats was characterized by the presence of interstitial exudates, degeneration, and necrosis of spermatogenic and interstitial (Leydig) cells. Findings indicate that exposure of male rats to Nigerian Qua Iboe Brent crude oil may have adversely affected their reproductive systems. This may imply possible reproductive health hazards for animals and humans that may be exposed to this environmental pollutant, especially in areas where oil spillage is a common feature.     

Resveratrol supplementation into extender protects against cryodamage in dog post-thaw sperm

Antioxidants have multiple protective roles in a variety of cells and thus can be used to protect sperm against cryo-damage during freezing, which affects fertility. The antioxidant resveratrol (3,5,4-trihydroxytrans-stilbene; RSV) has been reported to protect the animal sperm during cryopreservation, including human sperm. In this study, we assessed the protective effects of RSV supplementation on dog sperm cryopreservation. Semen was collected from four dogs and the effect of different concentrations of RSV (0, 100, 200, and 400 µM) on post-thaw sperm quality was examined. After thawing, sperm motility was assessed using computer-aided sperm analysis, and the structural integrity of the plasma membrane, acrosome, and chromatin was examined. In addition, their mitochondrial activity and gene expression were also assessed. Dog sperm cryopreserved with 200 µM RSV showed significant improvement in post-thaw sperm motility and viability compared with that of the control group (P<0.05). Moreover, RSV-supplemented samples showed significantly higher numbers of sperm with an intact plasma membrane, active mitochondria, and structural integrity of acrosomes and chromatin than that of control samples (P<0.05). Furthermore, gene expression showed that RSV supplemented samples showed lower expression of pro-apoptotic (BAX), reactive oxygen species (ROS) modulator oxidative stress-related (ROMO1) and 8-oxoguanine DNA glycosylase 1 (OGG1) whereas higher expression levels of anti‐apoptotic (BCL2), protamine-2 (PRM2), protamine-3 (PRM3) and sperm acrosome‐associated 3 (SPACA3) genes than control. Our results suggest that RSV, at its optimum concentration, can be efficiently used as an antioxidant in the cryopreservation of dog sperm.     

Potential of triptolide in reproductive management of the house rat,Rattus rattus

Mature and healthy male house rats, Rattus rattus (n= 160) were fed on bait (cracked wheat: powdered sugar, 98:2) containing different concentrations of triptolide (0.1, 0.05, 0.025 and 0%) for 7 and 14 days in no‐choice and bi‐choice feeding tests in the laboratory. The objective of the study was to record the antifertility affects of triptolide after 30 and 60 days of termination of treatment. Results revealed no significant effect of triptolide treatment on weights of testis, epididymis, seminal vesicles and prostate gland of rats. Overall, sperm motility, live sperm count, sperm density and sperm morphology in the cauda epididymal fluid were found to differ significantly (P≤ 0.05) between untreated and treated groups of rats. The major effect of triptolide on sperm morphology was in the form of sperm head tail separation, which was up to 56.0% in rats treated for 14 days in no‐choice and autopsied after 30 days. A significant effect (P≤ 0.05) of triptolide treatment was observed on the histomorphology of the testis, which included a dose‐dependent decrease in diameter of seminiferous tubules, thickness of germinal epithelium and numbers of various spermatogenic cells. Cell associations in the seminiferous epithelial cycle were poorly developed in rats ingesting medium (4.7–5.1 mg/100 g bw) and high doses (6.9–7.2 mg/100 g bw) of triptolide than rats ingesting low doses (1.8–2.3 mg/100 g bw) and untreated rats. The cell stages affected had not recovered fully within the 60 day period following triptolide withdrawal. The present study suggests the potential of triptolide in reproductive management of Rattus rattus.     

Addition of D-penicillamine,hypotaurine, and epinephrine (PHE) mixture to IVF medium maintains motility and longevity of bovine sperm and enhances stable production of blastocysts in vitro

The present study aimed to establish an efficient system for bovine embryo production by in vitro fertilization (IVF) that can achieve stable normal fertilization and blastocyst developmental rates in any bull without optimization of the sperm concentration in IVF medium. We examined the effects of a PHE mixture (20 μM D-penicillamine, 10 μM hypotaurine and 1 μM epinephrine), theophylline (2.5 mM), and sperm concentration (1, 2 or 5 × 10⁶ cells/ml) on fertilization and blastocyst developmental rates. High cleavage rates (78.3 to 92.4%) and blastocyst developmental rates (31.9 to 62.0%) at day 7 were obtained in the presence of PHE and theophylline in IVF medium with a sperm concentration of 2 × 10⁶ cells/ml using sperm from 9 bulls. In addition, the synergistic effect of PHE and theophylline on normal fertilization (2 pronuclei) was clarified at 12 h after IVF with a sperm concentration of 1 × 10⁶ cells/ml. Moreover, high linearity, high flagellar beat cross frequency, and low amplitude of lateral head of motile sperm were found by computer-assisted sperm analysis. In conclusion, the combination of the PHE mixture and theophylline synergistically accelerates sperm motility and sperm penetration of bovine oocytes. Theophylline activates sperm motility with increasing intracellular cAMP. However, PHE prevents an excessive increase of cAMP and maintains sperm motility without hyperactivation. When the combination of PHE and theophylline is added to IVF medium at a sperm concentration of 2 × 10⁶ cells/ml, we can achieve stable normal fertilization and blastocyst development in any bull.     

Testicular Volume and Daily Sperm Output in Ragusano Donkeys

A careful evaluation of daily sperm output (DSO) and seminal parameters is indicative of the potential fertility of the animal and at the same time is useful for maximization of the reproductive activity. The aim of this article was to evaluate the seminal parameters, testicular volume (TV) calculated by ultrasound measurements, DSO, and any eventual relationship between these in Ragusano donkey jackasses. Eight Ragusano donkey stallions underwent a morphometric evaluation of the testes by ultrasound to calculate the TV, and daily semen collection for 10 consecutive days. TV ranged from 250 to 500 cm³ and no significant differences could be observed between the left and right testes. Only ejaculates from 4 to 10 days were analyzed, given that there was evidence that the sperm extragonadal reserve interfered with the total number of sperm in ejaculates during the early days. DSO in the Ragusano donkey ranged from 7 to 23 × 10⁹ sperms. The seminal parameters showed high values of motility, viability, and low abnormality percentages. Age, TVs, and sperm parameters were not significantly correlated. The correlation between TV and DSO was poor (P = .1) in this study and this may suggest that TV and DSO might simply not be highly correlated in the donkey.     

牛卵母细胞体外受精技术研究

本研究从3方面进行了牛卵母细胞的体外受精试验,即用不同离心法、不同温度上浮法、不同精子浓度等方法对COCs进行体外受精,测定其体外受精率。结果表明,两种离心法中,以上清液二次离心法的精子获能效果最好,受精率最高,该法首次采用低速离心技术,突破了离心法的传统方法,离心效果明显提高;不同温度条件下的精子上浮效果以CO2培养箱恒温（38.5℃）上浮法最好,受精率最高;对于选择受精时获能精子的浓度,宜控制在1.0×106～1.5×106个/ml,不仅能提高受精率,还可避免或降低多精受精现象。     

Relationship between sperm quality traits and field-fertility of porcine semen

An investigation involving seven boars, active in artificial insemination, and 1,350 multiparous sows was conducted at a private farm and aimed at examining the relationship between sperm quality traits and boar fertility in terms of farrowing rate and litter size. This experiment was done for 6 months. The semen samples were evaluated for subjective sperm motility and concentration. Ejaculates with at least 1 × 10⁸ sperm/mL and 70% sperm progressive motility were extended with a commercial medium to 30 × 10⁶ sperm/mL and used for artificial insemination (AI). AI dose was 100 mL semen containing 3 × 10⁹ spermatozoa. Aliquots of diluted semen were assessed for live morphologically normal spermatozoa (LMNS, eosin-nigrosin stain exclusion assay) and sperm chromatin instability (SCI, acridine orange assay). Farrowing rates according to different boar sperm varied (p < 0.001) from 59.3 to 88.92%. The mean values of LMNS (47.2~76.5%) and SCI (0.16~4.67%) differed significantly among boars. LMNS (r = 0.79, p < 0.05) and SCI (r = -0.90, p < 0.02) accounted for 62.2 and 81.7% of the variability in farrowing rates, respectively. After the combination of sperm traits, the relationship between percentage of LMNS with stable chromatin structure and farrowing rate was significant (r = 0.86, p < 0.05). The number of live piglets per parturition was not significantly correlated with sperm quality attributes. In conclusion, boar fertility after AI with freshly diluted semen can be predicted based on the evaluation of sperm morphology and chromatin integrity.     

公牛精子在四种介质中的品质变化

６头荷斯坦成年公牛，每头采集３次精液，分别利用精子穿透试验和姬姆萨染色法，评定精子在发情母牛子宫颈粘液、ＶＢ１２、稀释液和解冻液等四种介质中的泳动速度、顶体完整车、畸形率以及精子有效存活时间的变化。结果表明，精子泳动速度在不同介质中的差异极显著，在宫颈粘液中显著高于其它介质，在ＶＢ１２中最低；不同介质中精子顶体完整率的差异不明显；畸形率在ＴＢ１２中显著低于解冻液；精子有效存活时间在稀释液和解冻液中显著高于ＶＢ１２中。不同公牛在四种介质中的反应亦有一定差异。     

Effects of sulfanilamide on boar sperm quality,bacterial composition,and fertility during liquid storage at 17°C

Sulfanilamide (SA) is an effective broad‐spectrum antibacterial agent in human and veterinary medicine. The purpose of this study was to evaluate the effects of SA on boar sperm quality during liquid storage at 17°C and determine the optimal concentration of SA and its effects on bacterial growth, microbial composition, and maternal fertility. Boar ejaculates were diluted with a basic extender, containing different concentrations of SA, and stored in a 17°C incubator for 6 days. The sperm motility, plasma membrane integrity, and acrosome integrity were measured daily. The results showed that when the concentration of SA was 0.02 g/L, the sperm quality parameters were significantly higher than those of all other treatment groups (p < .05). We also monitored the bacterial growth and compared the differences in the microbial species between the 0.02 g/L SA group and the control by 16S rDNA sequencing. The results revealed that some bacteria, such as Staphylococcus and Pseudomonas, were considerably lower in the 0.02 g/L SA group than in the control group (p < .05). In addition, preserved semen was used for artificial insemination, and results showed that 0.02 g/L SA group had a higher litter size, and its pregnancy rate was 92.5%.     

Reproduction in the Rock Hyrax (Procavia Capensis)

Irradiation has adverse effects on reproductive aspects such as spermatogenic cell population and cell malformation, leading to reduced sperm count and non-viable spermatozoa. This has overshadowed possible effects of radiation exposure on biochemical environment throughout the epididymis and the viability of spermatozoa that appeared morphologically normal. The effects of radiation exposure on sperm quality were evaluated through mating trials and assessment of the cauda epididymal sperm motility. Sprague Dawley rats with body mass of 300–400 g were selected at random. Two experimental groups received acute ⁶°Co γ-radiation doses of 3.5 and 6.0 Gy, respectively. Data were collected 2, 7, 14, 21, 28 and 35 days post-irradiation. Each male was housed with a non-irradiated super-ovulated female during mating trials. Cauda epididymal sperm motility was assessed with the CASMA. Hormone analyses were carried through chemiluminescence diagnostic tests to determine the endocrine status. Results suggest that irradiation causes an overproduction of estrogens, which suppresses the hypothalamic-pituitary axis and inhibits LH and FSH secretions. Both LH and FSH deficiencies have negative effects on the testicular index and local reproductive hormones. Elevated estrogen levels influenced the epididymal internal milieu negatively, resulting in rigid, flagella bending sperm tail, impaired progressive movement of the spermatozoa and hence infertility     

Sperm production and quality in European eel (Anguilla anguilla) in relation to hormonal treatment

Aquaculture production relies on controlled management of gametogenesis, especially in species where assisted reproduction is needed for obtaining gametes in captivity. The present study used human chorionic gonadotropin (hCG) treatments to induce and sustain spermatogenesis in European eel (Anguilla anguilla). The aim was to evaluate effects of strip-spawning timing (12 vs. 24 hr) after weekly administration of hCG and the necessity of a primer dose (in addition to weekly hormonal treatment) prior to strip spawning (primer vs. no-primer) on sperm quality parameters. Sperm parameters included milt production (weight), density and sperm kinematics at Week 9, 11 and 13 after onset of treatment. Spermiation commenced in 11.5% of males in Week 5 and by Week 9, and all males produced milt. Male weight, milt production, sperm density and spermatocrit did not differ among hormonal treatments during the experimental period. Overall, male weight decreased from 106.3 to 93.0 g, milt weight increased from 3.5 to 5.4 g, sperm density counts decreased from 11.7 × 10⁹ to 10.5 × 10⁹ cells/ml, and spermatocrit decreased from 46.5% to 40.5%. Furthermore, spermatocrit was positively related to haemocytometer counts (R² = .86, p < .001), providing a reliable indicator of sperm density. Differences in sperm kinematics were observed depending on strip-spawning timing after hormonal injection (12 vs. 24 hr) but with no consistent pattern. These sperm quality parameters also did not consistently differ between the no-primer and primer treatments. Considering that each male may be stripped 4–5 times over the 2–3 months spawning season, omitting the primer would reduce animal handling, material costs and labour intensity, while sustaining high-quality sperm production.     

Effects of the supplementation with an high‐polyphenols extra‐virgin olive oil on kinetic sperm features and seminal plasma oxidative status in healthy dogs

The aim of this work was to evaluate the effects of the supplementation of two extra‐virgin olive oils (EVOO) having different polyphenols content, on canine spermatozoa kinetic parameters and seminal plasma oxidative status. The study was conducted on 12 clinically healthy dogs of different breeds (2–7 years, 5–48 kg of body weight) divided into two groups: an experimental group supplemented with EVOO (Coratina cultivar) high in polyphenols (H‐P) and a control group fed EVOO (Cima di Bitonto cultivar) low in polyphenols (L‐P). The oil was daily administered per os (1 ml/3 kg BW) before meal. Semen collection was made twice at 15 days distance (D0₁ and D0₂) and then at 30 (D30), 60 (D60) and 90 (D90) days. Semen concentration and kinetic parameters were measured using computer‐assisted sperm analysis (CASA) system to evaluate: sperm total count, sperm motile (MOT%), progressive motility (PROGR%) and its fractions, straight‐line velocity (VSL, μm/s), curvilinear velocity (VCL, μm/s), average path velocity (VAP, μm/s), amplitude of lateral head displacement (ALH, μm), beat cross frequency (BCF, Hz), straightness (STR%) and linearity (LIN%). On seminal plasma, reactive oxygen species (ROS) and biological antioxidant potential (BAP) were tested. From findings, no differences were found for sperm MOT, VSL, VCL, VAP, ALH, BCF, STR, LIN and BAP. A gradual enhancement of PROGR% was observed in H‐P group (p < .01). The ROS levels were higher in dogs H‐P compared to the other group (p < .05). In conclusion, our results highlight the positive effects of EVOO polyphenols on sperm PROGR% in healthy dogs.     

Assessment of chosen semen characteristics of two colour morphs of the Arctic fox Alopex lagopus L.

The aim of the study was to evaluate semen quality in the two most popular colour morphs of the Arctic fox Alopex lagopus L., blue and white, based on ejaculate parameters, acrosin activity and analysis of sperm morphology. The research material consisted of ejaculates collected once by manual stimulation from 20 one‐year‐old male Arctic foxes (10 individuals of the blue morph and 10 of the white morph). Ejaculates were evaluated in terms of volume, sperm concentration, total number of spermatozoa and the percentage of spermatozoa with major and minor defects. The study revealed that male blue Arctic foxes produce ejaculates with much higher concentration (148.75 × 10⁶/ml) and total number of spermatozoa (98.16 × 10⁶) compared to white Arctic foxes (42.88 × 10⁶/ml and 35.2 × 10⁶ respectively). The level of acrosin activity from white foxes seemed to be higher compared to blue foxes but the difference was not statistically confirmed. Semen from Arctic foxes is characterized by high inter‐individual variability in sperm morphology. The frequency of morphological changes in sperm from Arctic foxes does not significantly depend on ejaculate volume, sperm concentration or the total number of spermatozoa in the ejaculate, but is associated with acrosin activity.     

Effects of the Addition of Autologous Seminal Plasma to Highly Concentrated Stallion Semen After 48 Hours of Cooled Storage

Insemination with chilled transported semen has become distinctly important in the horse-breeding industry. To ensure cell survival during cooled storage, semen is diluted with an appropriate extender and the concentration of seminal plasma (SP) is reduced. Nevertheless, SP plays an important immunomodulatory role in the female genital tract and supports sperm fertility. The aim of the present study was to evaluate the effect of the addition of autologous SP after cooled storage to highly concentrated stallion semen. Therefore, SP was removed by simple centrifugation of extended semen, aspiration of the supernatant, and resuspension of the sperm pellet with semen extender. Motion characteristics were evaluated after cooled storage for 48 hours at concentrations of 333 × 10⁶ sperm/mL in comparison with stored samples at concentration of 25 × 10⁶ sperm/mL (control). The highly concentrated semen samples were diluted with an extender containing 0%, 5%, 20%, and 80% SP directly before motility analysis. Dilution of the cooled semen with a fresh semen extender without SP (0%) increased kinematic parameters (curvilinear velocity [VCL] 137.3 vs. 151.8; straight-line velocity [VSL] 49.0 vs. 57.5; average path velocity [VAP] 69.5 vs. 79.4 μm/second; amplitude of lateral head [ALH] 3.1 vs. 3.3 μm; beat cross frequency [BCF] 31.6 vs. 33.5 Hz; P < .05) but not total motility (51% vs. 43%) and progressive motility (46% vs. 36%) compared with controls. The addition of SP after storage for 48 hours decreased sperm total motility and progressive motility regardless of SP concentration: 5 (38% and 34%), 20 (37% and 33%), and 80% SP (27% and 22%; P < .05). In contrast, kinematic parameters were enhanced by extenders containing 5% and 20% SP (VCL: 148.0 and 155.6; VSL: 59.2 and 60.9; VAP: 78.7 and 81.9; BCF: 33.4 and 35.7; ALH: 3.4 and 3.4; P < .05). However, using an extender containing 80% SP was detrimental to kinematic parameters (VCL: 151.2; VSL: 52.2; VAP: 76.9; BCF: 34.8; P < .05) except for ALH, which increased (3.5; P < .05). In conclusion, cooled storage at concentrations of 333 × 10⁶ sperm/mL did not affect sperm motility. The addition of a fresh extender or an extender containing small concentrations of SP to highly concentrated ejaculated sperm increased kinematic values after storage; however, increasing concentrations of SP decreased sperm motility.     

Retracted: Effects of multiple collections on spermatozoa quality of Persian sturgeon,Acipenser persicus: motility,density and seminal plasma composition

In this study, we investigated the effects of multiple collections of sperm on the endangered Persian sturgeon, Acipenser persicus, in terms of a number of sperm functional parameters (percentage of motile spermatozoa, total time period of motility and sperm concentration) as well as on the ionic composition, protein concentration and osmolality of seminal plasma. Semen samples were collected from 12 induced male fish in three experimental groups that had been injected intramuscularly with LHRH‐A₂, at dosages of 5 μg/kg body weight, at a number of time regimes: at 12 h, 17 h and 24 h after spawning induction (1); at 24, 29 and 34 h after spawning induction (2); and at 36, 41 and 46 h after spawning induction (3). The percentage of motile spermatozoa and the period of sperm motility decreased significantly (p < 0.05) after the second and third collections. The concentration of spermatozoa decreased after the third collection, but this decline was not significant. No significant effect of multiple collections on protein concentration and ionic content (with exception of the Cl^? ion) of seminal plasma was observed. In all experimental groups, a moderate impact of sequential collection on the osmolality (p < 0.05) of seminal plasma was observed. This study provides new data on the effects of multiple collections on spermatological characteristics in the Persian sturgeon. Our results confirm that sequential stripping after the third collections has a negative effect on a number of functional parameters associated with sperm.     

Rosmarinic acid improves boar sperm quality,antioxidant capacity and energy metabolism at 17°C via AMPK activation

Boar sperm are susceptible to oxidative damage caused by reactive oxygen species (ROS) during storage. Adenosine monophosphate (AMP)-activated protein kinase (AMPK) is an important therapeutic target, because it is a cellular metabolism energy sensor and key signalling kinase in spermatozoa. We evaluated the effects of rosmarinic acid (RA), an antioxidant, on boar sperm during liquid storage to determine whether it protects boar sperm via AMPK activation. Boar ejaculates were diluted with Modena extender with different concentrations of RA and stored at 17°C for 9 days. Sperm quality parameters, antioxidant capacity, energy metabolism, AMPK phosphorylation and fertility were analysed. Compared with the control, 40 μmol/L significantly improved sperm motility, plasma membrane integrity and acrosome integrity (p < .05). The effective storage time of boar sperm was up to 9 days. On the third and seventh days, the sperm with RA exhibited increased total antioxidant capacity (T-AOC), superoxide dismutase (SOD) activity, adenosine triphosphate (ATP) content, mitochondrial membrane potential (ΔΨm) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) activity, whereas malondialdehyde (MDA) content was significantly decreased (p < .05). Western blot showed that RA, as well as AICAR (AMPK activator), promoted AMPK phosphorylation, whereas Compound C (AMPK inhibitor) inhibited this effect. The sperm–zona pellucida binding experiment showed that 40 μmol/L RA increased the number of sperm attached to the zona pellucida (p < .05). These findings suggest meaningful methods for improved preservation of boar sperm in vitro and provide new insights into the mechanism by which RA protects sperm cells from oxidative damage via AMPK activation.     

Effect of different mini‐volume colloid centrifugation configurations on flow cytometrically sorted sperm recovery efficiency and quality using a computer‐assisted semen analyzer

Straws of sex‐sorted sperm are usually packaged at a low concentration (e.g., ~2.1 × 10⁶ sperm/ml) and cost significantly more than unsorted conventional semen from the same sire. In order to maximize the efficiency of using sex‐sorted sperm under in vitro fertilization conditions, the selection of an appropriate sperm separation technique is essential. In this study, the effect of using different silane‐coated silica colloid dilutions and layering configurations during centrifugation of sex‐sorted sperm was examined over an extended period of incubation time. Sperm recovery and viability after centrifugation using the colloid separation technique were measured along with several sperm motility parameters using CASA. For this purpose, frozen and thawed sex‐sorted sperm samples were centrifuged using mini‐volume single‐layer (40%, 60% and 80%) and mini‐volume two‐layer (45%/90%, 40%/80% and 30%/60%) separation configurations using PureSperm^®. A single layer of 40% PureSperm^® recovered significantly more sex‐sorted sperm (78.07% ± 2.28%) followed by a single layer of 80% PureSperm^® (68.43% ± 2.33%). The lowest sperm recovery was obtained using a two‐layer PureSperm^® dilution of 45%/90% (47.57% ± 2.33%). Single‐layer centrifugation recovered more sorted sperm (68.67% ± 1.74%) than two layer (53.74% ± 1.74%) (p < .0001). A single layer of 80% PureSperm^® exhibited the highest sorted sperm viability (72.01% ± 2.90%) after centrifugation (p < .05). The mini‐volume single layer of 80% PureSperm^® was determined to be an effective alternative to a two‐layer centrifugation configuration for sex‐sorted sperm selection. In addition, single‐layer colloid dilution of 80% performed either as well as or significantly outperformed the other treatments, as well as the control, with regard to motility (MOT) for all time periods of analysis.     

Mobility of Japanese quail spermatozoa and its relationship to egg fertility

Sperm mobility (SM) appears to be primary determinant of fertility in chicken and turkey. The aims of this study were to extend the concept to the Japanese quail by developing an assay to quantify SM, explaining the basis of SM using motility properties measured by CASA, and exploring the relationship between SM and egg fertility. The study was carried out in three stages: i) males (n = 20) and females (n = 20) were mated individually; ii) ejaculates were collected from 20 males, and SM was measured; iii) males (n = 20) and females (n = 20) were mated individually. In Stages I and III, data were collected for egg fertility, Sperm_OPVL and Holes_IPVL. In Stage II, SM assay was developed and assay conditions were defined: effect of sperm numbers on absorbance in Accudenz solution; effect of Accudenz concentration on sperm motility and mobility; effect of quail proctodeal gland foam extract and incubation temperature on SM at 37 and 41°C. The recorded absorbance of sperm movement was dependent on sperm numbers in the sperm suspension overlaying the Accudenz (p < .001). At 41°C, SM, progressively motile sperm, VCL, VSL and VAP were negatively affected by Accudenz concentration (p < .05). The effect of foam on SM and motility depended on an interaction between the concentration of foam extract and incubating temperature. Males were categorized into low, average and high SM phenotypes. These categories differed significantly (p < .001), but sperm motility and SM were not related to egg fertility. In conclusion, SM assay can be used to identify mobility phenotypes, but the poor relationship between SM and egg fertility indicates a need for further studies on interaction between the concentration of foam extract, incubating temperature, and in vivo sperm movement and egg fertilization success.     

Effects of breed and ejaculate volume on sperm morphology and semen parameters of boars

The aim of the study was to determine the relation between the semen quality, frequency of sperm defects, sperm dimensions and shape, and the ejaculate volume of Large White and Landrace boars. A total of 648 ejaculates collected from 31 Large White and 30 Landrace boars were divided into three groups according to the criterion of the ejaculate volume. In this study Landrace boars produced ejaculates with higher volume, sperm concentration, and total numbers of spermatozoa than Large White boars. Landrace boars also showed a lower frequency of sperm with morphological abnormalities (P < 0.05). Landrace boars sperm had larger heads, which were by 0.15 μm longer, and by a larger perimeter and area (P < 0.05). Landrace boar spermatozoa also had a longer flagellum and were generally larger and by 2.07 μm longer than Large White boar sperm (P < 0.05). Significant differences were also found in the shape of sperm of the two breeds (P < 0.05). Landrace boars sperm had more elongated heads, and the ratio of head size to flagellum length was lower than in Large White boars sperm (P < 0.05). Sperm from ejaculates with low volume had a shorter flagellum and a greater head length/flagellum length ratio than sperm from medium- and high-volume ejaculates (P < 0.05).     

Impact of proximal cytoplasmic droplets on quality traits and in-vitro embryo production efficiency of cryopreserved bull spermatozoa

Background

Proximal cytoplasmic droplets (PCDs), a remnant of germ cell cytoplasm, are common non-specific morphological defects in bovine semen. This study evaluated the effect of higher percentages of PCDs on the quality of frozen-thawed bovine semen, embryo production and early embryo development.

Methods

Three ejaculates from each of five (group 1: PCD ≤ 1%, control) and eight adult Bos indicus bulls (group 2: PCD ≥ 24%) were analysed. Semen samples were examined for: post-thaw motility, vigour of movement, concentration, sperm morphology, slow thermoresistance test (STT), membrane integrity, acrosome status, mitochondrial function using fluorescent probes association (FITC-PSA, PI and JC-1) and sperm chromatin integrity using acridine orange assay. Two bulls from group 2, with 28.5% and 48.5% PCD, respectively, and three bulls from the control group, each with 0% PCD, were selected for IVF (in vitro fertilisation).

Results

Semen analyses revealed a significant correlation (P < 0.01) between increased rates of PCD and sperm quality traits. Nevertheless, no differences were observed in sperm motility and vigour either before or after the STT or in the percentage of intact acrosomes (analysed by differential interference contrast microscopy (DIC) after STT), but membrane integrity, acrosome status (evaluated with FITC-PSA staining method after thawing) and mitochondrial function were reduced, when compared with group 1 (P < 0.05). The higher incidence of PCD was positively correlated to chromatin damage, especially after three hours of incubation at 37°C. IVF showed similar results for bull C2 (group 1, control) and bull P2 (group 2, group with higher PCDs).

Conclusion

Higher PCD levels influenced spermatozoa quality traits. IVF and embryo development data showed that cleavage, blastocyst formation and blastocyst hatching may have been influenced by the interaction of morphology traits and individual bull effects.